This section is intended to introduce various aspects of the art, which may be associated with exemplary embodiments of the present disclosure. This discussion is believed to assist in providing a framework to facilitate a better understanding of particular aspects of the present invention. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.
In hydrocarbon exploration, development, and/or production operations, different types of subsurface models may be used to represent subsurface structures, which may include a description of the subsurface structures and material properties for the subsurface region. For example, the subsurface model may comprise one or more of a geomechanical model, a geologic model, or a reservoir model. The subsurface model may represent measured or interpreted data for the subsurface region and may include objects (e.g., horizons, faults, surfaces, volumes, and the like). The subsurface model may also be discretized with a mesh or a grid that includes nodes and forms cells (e.g., voxels or mesh elements) within the model. By way of example, the subsurface model may be created from a structural framework (e.g., organization of objects) and provide defined compartments or subvolumes. The geologic model may represent measured or interpreted data for the subsurface region, such as seismic data and well log data. The geologic model may be within a physical space or domain and may have material properties, such as rock properties. The reservoir model may be used to simulate flow of fluids within the subsurface region. Accordingly, the reservoir model may use the same mesh and/or cells as other models, or may resample or upscale the mesh and/or cells to lessen the computations for simulating the fluid flow.
In the subsurface regions represented by the subsurface model, various fractures and other structures may be present. For example, natural fractures may be present and provide additional impact on the flow of fluids through the reservoir. As a result, natural fractures may influence the movement, storage, and recovery of hydrocarbons. However, for subsurface regions with limited information, it can be difficult and problematic to predict fracture characteristics.
As an example, curvature analysis may be used to provide fractures, which uses current time period information. As a specific example, Keating describes that curvature analysis is typically utilized to predict the location and characteristics of fracture networks. See, e.g., Keating D. P., and Fischer, M. P., 2008, An experimental evaluation of the curvature-strain relation in fault-related folds, AAPG Bulletin v. 92, no. (7), 20 p. 869-884. However, curvature analysis may be problematic because it relies on 2D or 3D restoration or curvature analyses which may have limited power for fracture prediction. That is, the curvature analysis does not represent the entire macromechanical deformation process, as it does not involve simulating load. As a result, curvature analysis may be limited and may not always be used as a direct proxy for strain, as the dip and throw may be crucial factors. Additionally, it is difficult to qualitatively correlate the curvatures with fracture density and interaction during fracture genesis as loads change.
Accordingly, there remains a need in the industry for methods and systems that are more efficient and may lessen problems associated with characterizing fractures in a subsurface model (e.g., a geomechanical model, a geologic model, or a reservoir model) for use in hydrocarbon operations. Further, a need remains for efficient approaches to generate subsurface models that characterize natural fractures by using physics-based numerical methods to simulate the genesis of natural fractures. The present techniques provide methods and systems that overcome one or more of the deficiencies discussed above.